U.S. patent number 9,162,568 [Application Number 14/339,692] was granted by the patent office on 2015-10-20 for drive shaft detection for pump or motor protection.
This patent grant is currently assigned to Parker-Hannifin Corporation. The grantee listed for this patent is Parker-Hannifin Corporation. Invention is credited to Guobiao Song, Yisheng Zhang.
United States Patent |
9,162,568 |
Song , et al. |
October 20, 2015 |
Drive shaft detection for pump or motor protection
Abstract
A method of operating a vehicle includes the steps of: entering
a drive shaft test mode; receiving a command to position a yoke to
drive the shaft; regulating the shaft speed so as to be below a
predefined threshold; and determining whether a drive shaft is
available based on whether an actual drive shaft speed is detected
above the predefined threshold. When the detected actual drive
shaft speed is above the predefined threshold, it is determined
that the drive shaft is not available and the vehicle is disabled
to prevent damage to the vehicle. When the detected actual drive
shaft speed is not above the predefined threshold, it is determined
that the drive shaft is available, and the vehicle may be operated
as is typical. The methods may be performed by an controller
executing program code stored on a non-transitory computer readable
medium.
Inventors: |
Song; Guobiao (Dublin, OH),
Zhang; Yisheng (Dublin, OH) |
Applicant: |
Name |
City |
State |
Country |
Type |
Parker-Hannifin Corporation |
Cleveland |
OH |
US |
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Assignee: |
Parker-Hannifin Corporation
(Cleveland, OH)
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Family
ID: |
51212746 |
Appl.
No.: |
14/339,692 |
Filed: |
July 24, 2014 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20150032327 A1 |
Jan 29, 2015 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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61858229 |
Jul 25, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01M
13/02 (20130101); B60K 17/10 (20130101); B60K
23/08 (20130101); F16H 61/12 (20130101); B60K
23/00 (20130101); G01M 17/007 (20130101); F16H
2061/1208 (20130101); F16H 59/40 (20130101) |
Current International
Class: |
G01M
17/00 (20060101); G01M 17/007 (20060101); G06F
7/00 (20060101); B60K 23/00 (20060101); F16H
59/40 (20060101); G01M 13/02 (20060101) |
Field of
Search: |
;701/33.9 |
References Cited
[Referenced By]
U.S. Patent Documents
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5608626 |
March 1997 |
Ibamoto et al. |
6293085 |
September 2001 |
Thompson et al. |
8140207 |
March 2012 |
Nozaki et al. |
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Foreign Patent Documents
Other References
European Search report for corresponding European Application No.
14178129.4 dated Mar. 30, 2015. cited by applicant.
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Primary Examiner: Anwari; Maceeh
Attorney, Agent or Firm: Renner, Otto, Boisselle &
Sklar, LLP
Parent Case Text
RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application
No. 61/858,229, filed Jul. 25, 2013, which is incorporated herein
by reference.
Claims
What is claimed is:
1. A method of operating a vehicle having a drive shaft test mode
comprising the steps of: entering the drive shaft test mode;
receiving a command to position a yoke to drive the shaft;
regulating the shaft speed so as to be below a predefined
threshold; and determining whether a drive shaft is available based
on whether an actual drive shaft speed is detected above the
predefined threshold wherein when the detected actual drive shaft
speed is above the predefined threshold, determining that the drive
shaft is not available; further comprising disabling the vehicle
when it is determined that the drive shaft is not available.
2. The method of operating a vehicle of claim 1, further comprising
generating a fault message that alerts a vehicle operator that the
drive shaft is not available.
3. The method of operating a vehicle of claim 2, wherein when the
detected actual drive shaft speed is not above the predefined
threshold, determining that the drive shaft is available and
operating the vehicle with the drive shaft limiting the speed.
4. The method of operating a vehicle of claim 1, wherein the step
of entering the drive shaft test mode comprises the steps of:
detecting a shift event of a vehicle transmission; determining
whether the shift event is a shift from neutral to in-gear
following initial startup of the vehicle; and when it is determined
that the shift event is a shift of the transmission from neutral to
in-gear following the initial startup of the vehicle, entering the
drive shaft test mode.
5. The method of operating a vehicle of claim 4, wherein the step
of determining whether the shift event is a shift from neutral to
in-gear following the initial startup of the vehicle comprises the
steps of: detecting conditions of whether the shift event (a) is
the first shifting, (b) occurred within the last three seconds, (c)
occurred with the accelerator not pressed, and (d) occurred with
the parking brake applied and the vehicle not moving; and
determining that the shift event is a shift from neutral to in-gear
following the initial startup of the vehicle when all of conditions
(a)-(d) are satisfied.
6. The method of operating a vehicle of claim 1, further
comprising, after the step of entering the drive shaft test mode,
the steps of: detecting whether an exit condition is present; and
exiting the drive shaft test mode when the exit condition is
present.
7. The method of operating a vehicle of claim 6, wherein the exit
condition comprises at least one of whether the accelerator is
pressed, whether the parking brake is released, whether the vehicle
has shifted out of hydraulic gears, or whether the drive shaft
speed already is detected above the predefined threshold.
8. A control system for operating a vehicle having a drive shaft
test mode comprising: a sensor system for detecting a drive shaft
speed; and a controller configured to determine whether a drive
shaft is available based on whether an actual draft shaft speed
detected by the sensor system is above a predefined threshold
wherein when the detected actual drive shaft speed is above the
predefined threshold, the controller determines that the drive
shaft is not available; further comprising one or more vehicle
components that when disabled, disable a vehicle; wherein when the
controller determines that the drive shaft is not available, the
controller causes one or more of said vehicle components to disable
the vehicle.
9. The control system of claim 8, further comprising an indicator
output device; wherein when the controller determines that that the
drive shaft is not available, the controller causes the indicator
output device to generate a fault message that alerts a vehicle
operator that the drive shaft is not available.
10. A non-transitory computer readable medium storing executable
program code, which when executed by a controller is configured to
perform the steps of: entering the drive shaft test mode; receiving
a command to position a yoke to drive the shaft; regulating the
shaft speed so as to be below a predefined threshold; and
determining whether a drive shaft is available based on whether an
actual drive shaft speed is detected above the predefined threshold
wherein when the detected actual drive shaft speed is above the
predefined threshold, the program code is executed to determine
that the drive shaft is not available; wherein the program code is
executed further to disable the vehicle when it is determined that
the drive shaft is not available.
11. The non-transitory computer readable medium of claim 10,
wherein when the detected actual drive shaft speed is not above the
predefined threshold, the program code is executed to determine
that the drive shaft is available such that the vehicle is operable
with the drive shaft limiting the speed.
12. The non-transitory computer readable medium of claim 10,
wherein the step of entering the drive shaft test mode comprises
executing the program code to perform the steps of: detecting a
shift event of a vehicle transmission; determining whether the
shift event is a shift from neutral to in-gear following initial
startup of the vehicle; and when it is determined that the shift
event is a shift of the transmission from neutral to in-gear
following the initial startup of the vehicle, entering the drive
shaft test mode.
13. The non-transitory computer readable medium of claim 10,
further comprising, after the step of entering the drive shaft test
mode, the program code is executed to perform the steps of:
detecting whether an exit condition is present; and exiting the
drive shaft test mode when the exit condition is present.
Description
FIELD OF INVENTION
The present invention relates generally to drive systems, controls,
and diagnostics for pumps and motors, particularly as may be used
in vehicle drive systems, and more particularly to methods and
systems for operating a vehicle in a test mode for detecting a
drive shaft.
BACKGROUND
In conventional vehicle transmission systems, the drive shaft is
removed for towing when the vehicle cannot be driven to a repair
shop. This presents a potential danger in that a repair or service
technician can forget to reinstall the drive shaft back into the
vehicle before the vehicle is driven again. If the drive shaft is
not reinstalled into the vehicle, subsequent driving could cause
severe damage to the vehicle power train and drive train
components. In absence of the drive shaft, such vehicle components
become susceptible to high rotation speeds because there is very
little counteracting inertia at the power train when drive shaft is
removed.
SUMMARY OF INVENTION
The present invention provides methods for operating a vehicle that
reduces the likelihood of vehicle damage that may be caused by
operating the vehicle without the drive shaft installed. In
particular, the invention provides methods and systems for
transmission control in which the availability (i.e., presence or
absence) of a drive shaft is detected. The availability of the
drive shaft is detected by operating the vehicle in a special test
mode of operation after initial gear shifting from neutral to
in-gear at the vehicle startup. If the drive shaft is not detected
based on the drive shaft test mode of operation, the vehicle is
disabled to protect vehicle components from damage due to
uncontrolled rotation.
An aspect of the invention, therefore, is a method of operating a
vehicle having a drive shaft test mode. In exemplary embodiments,
the method of operating a vehicle includes the steps of: entering
the drive shaft test mode; receiving a command to position a yoke
to drive the shaft; regulating the shaft speed so as to be below a
predefined threshold; and determining whether a drive shaft is
available based on whether an actual drive shaft speed is detected
above the predefined threshold. When the detected actual drive
shaft speed is above the predefined threshold, it is determined
that the drive shaft is not available and the vehicle is disabled
to prevent damage to the vehicle. When the detected actual drive
shaft speed is not above the predefined threshold, it is determined
that the drive shaft is available, and the vehicle may be operated
as typical.
The drive shaft test mode may be entered when it is determined that
a shift event is a shift of the transmission from neutral to
in-gear following the initial startup of the vehicle. For example,
such a shift event may be deemed to have occurred when the shift
event (a) is the first shifting, (b) occurred within the last three
seconds, (c) occurred with the accelerator not pressed, and (d)
occurred with the parking brake applied and the vehicle not moving.
The drive shaft test mode may be exited when an exit condition is
detected. For example, the exit condition may include at least one
of whether the accelerator is pressed, whether the parking brake is
released, whether the vehicle has shifted out of hydraulic gears,
or whether the drive shaft speed already is detected above the
predefined threshold.
Another aspect of the invention is a control system for operating a
vehicle having a drive shaft test mode. In exemplary embodiments,
the control system includes a sensor system for detecting a drive
shaft speed, and a controller configured to determine whether a
drive shaft is available based on whether an actual draft shaft
speed detected by the sensor system is above a predefined
threshold. The control system may be configured to perform the
described methods by executing a computer program stored on a
non-transitory computer readable medium.
These and further features of the present invention will be
apparent with reference to the following description and attached
drawings. In the description and drawings, particular embodiments
of the invention have been disclosed in detail as being indicative
of some of the ways in which the principles of the invention may be
employed, but it is understood that the invention is not limited
correspondingly in scope. Rather, the invention includes all
changes, modifications and equivalents coming within the spirit and
terms of the claims appended hereto. Features that are described
and/or illustrated with respect to one embodiment may be used in
the same way or in a similar way in one or more other embodiments
and/or in combination with or instead of the features of the other
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is schematic diagram depicting an exemplary vehicle in
accordance with embodiments of the present invention.
FIG. 2 is a flow chart diagram depicting an exemplary method of
operating a vehicle in a drive shaft test mode.
FIG. 3 is a flow chart diagram depicting an exemplary method of
entering the drive shaft test mode of operation of FIG. 1.
FIG. 4 is a flow chart diagram depicting an exemplary method of
exiting the drive shaft test mode of operation of FIG. 1.
FIG. 5 is a block diagram depicting operative components of a
control system for performing the methods of FIGS. 2-4.
DETAILED DESCRIPTION
Embodiments of the present invention will now be described with
reference to the drawings, wherein like reference numerals are used
to refer to like elements throughout. It will be understood that
the figures are not necessarily to scale.
FIG. 1 is schematic diagram depicting an exemplary vehicle 10. The
vehicle 10 generally includes an engine 12 coupled to a power drive
unit (PDU) 14. The PDU 14 includes a plurality of hydraulic pumps
16 that drive a gear train 18 in accordance with the gear selected
via the vehicle transmission system. The gear train 18 drives a
drive shaft 20 in response to a yoke position command, which in
turn causes the wheel axle 26 and associated wheels to turn.
The drive shaft 20 includes a first segment 22 adjacent the wheel
axle 26, and a second smaller segment 24 substantially contained
within the PDU 14. For towing, the first segment of the drive shaft
22 may be removed (which also is referred to herein more generally
as removal of the drive shaft), leaving only the smaller second
segment remaining within the PDU 14.
As referenced above, if the drive shaft is not reinstalled into the
vehicle, subsequent driving could cause severe damage to the
vehicle power train and drive train components. In absence of the
drive shaft, such vehicle components become susceptible to high
rotation speeds because there is very little counteracting inertia
at the power train when drive shaft is removed. The present
invention, therefore, provides methods and systems for transmission
control in which the availability (i.e., presence or absence) of a
drive shaft is detected. The availability of the drive shaft is
detected by operating the vehicle in a special test mode of
operation after initial gear shifting from neutral to in-gear at
the vehicle startup. If the drive shaft is not detected based on
the drive shaft test mode of operation, the vehicle is disabled to
protect vehicle components from damage due to uncontrolled
rotation.
FIG. 2 is a flow chart diagram depicting an exemplary method of
operating a vehicle in a drive shaft test mode. At step 100, the
drive shaft test mode is entered. At step 110, a command is
received to position the yoke to drive the shaft. Such command, for
example, is received when the driver would attempt to shift the
transmission from neutral to in-gear following the initial startup
of the vehicle. At step 120, in response to the yoke command, an
artificial torque command is generated to regulate the shaft speed
so as to be below a certain or predefined threshold.
As referenced above, however, if the drive shaft is not available
(particularly by removal of the first segment of the drive shaft
referenced above), the vehicle components, particularly of the
power train or drive train, would tend to rotate above the speed
commensurate with the intended drive shaft speed. Accordingly, at
step 130 a determination is made as to whether the actual drive
shaft speed is detected above the predefined threshold. In
particular, the speed of the second segment 24 of the drive shaft
remaining in the PDU 14 may be detected as the actual drive shaft
speed. With the removal of the first segment of the drive shaft,
the rotation of the second segment is not limited and the second
segment would tend to rotate well above the predefined
threshold.
If a "No" determination is made at step 130, i.e., the detected
speed indeed is not above the predefined threshold, it is deemed
that the drive shaft is present and preventing the second segment
from rotating. The method therefore proceeds to step 140 and
continues the test mode until an exit condition is satisfied. If,
however, a "Yes" determination is made at step 130, i.e., the
detected speed is above the predefined threshold, it is deemed that
the drive shaft is not present and available. The method therefore
proceeds to step 150, at which point the vehicle is disabled. The
vehicle is disabled so as to prevent damage to vehicle components
by driving in the absence of the entire drive shaft. A fault
message or indication also may be provided to alert the vehicle
operator that the drive shaft is absent and unavailable.
FIG. 3 is a flow chart diagram depicting an exemplary method of
entering the drive shaft test mode operation of FIG. 2. Generally,
the drive shaft test mode of operation should be entered when the
vehicle operator attempts to shift the transmission from neutral to
in-gear following the initial startup of the vehicle. Accordingly,
at step 200 a shift event occurs. Steps 210-240 essentially are
indicative of whether such shift event indeed is a shift of the
transmission from neutral to in-gear following the initial startup
of the vehicle. The method, therefore, detects whether the shift
event is the first shifting (step 200), occurred within the last
three seconds (step 220), occurred with the accelerator not pressed
(step 230), and occurred with the parking brake applied and the
vehicle not moving (step 240).
A "No" determination in any of steps 210-240 would tend to be
indicative that the drive shaft test mode should not be initiated.
In such case, the method proceeds to step 260 and normal vehicle
function proceeds. A "Yes" determination in all of steps 210-240,
however, would tend to be indicative that the shift event that
occurs at step 200 is indeed a shift of the transmission from
neutral to in-gear following the initial startup of the vehicle,
and the vehicle is in safe conditions to allow drive shaft
detection mode. In such case, the method proceeds to step 250 and
the drive shaft test mode of operation is entered.
FIG. 4 is a flow chart diagram depicting an exemplary method of
exiting the drive shaft test mode of operation of FIG. 2, as
indicated at step 140. Generally, the drive shaft test mode of
operation may be exited by driver action so the vehicle may be
operated immediately when the drive shaft test mode otherwise would
be performed. Accordingly, at step 300 it is presumed that the
vehicle already is within the drive shaft test mode of operation.
Steps 310-340 collectively constitute a step of detecting whether
one or more exit conditions is present for exiting the drive shaft
test mode. The method, therefore, detects whether the accelerator
is pressed (step 310), whether the parking brake is released (step
320), whether the vehicle has shifted out of hydraulic gears (step
330), and/or whether the drive shaft speed already is detected
above the predefined threshold (340). This last exit condition
essentially provides an indication that the drive shaft is not
present so the driver may be alerted, upon which the test mode is
complete and may be exited.
A "Yes" determination in any of steps 310-340 would tend to be
indicative that the driver wishes to exit the test mode while the
drive shaft test mode otherwise would be performed. In such case,
the method proceeds to step 360 and the drive shaft test mode is
exited. A "No" determination in all of steps 310-340, however,
results in the method proceeding to step 350, and the drive shaft
test mode is continued in accordance with FIG. 2.
FIG. 5 is a block diagram depicting operative components of a
control system 30 for performing the methods of FIGS. 2-4. The
control system 30 may include a controller 32 configured to control
the various operations of the components of the system 30. The
controller 32 may be configured as a processor device,
microprocessor, control circuit or the like device as are known in
the art. The controller further may be connected to a memory device
40. Although represented as a single memory device, the memory
device 40 may include one or more memory devices configured as
non-transitory comparable computer readable media as are known in
the art for storing executable computer program code. The
controller 32 may execute the program code to perform the method
steps of the operations of FIGS. 2-4 to cause the described methods
to be carried out. In exemplary embodiments, the controller is the
transmission controller for the transmission system.
A sensor system 34 may provide sensory inputs to the controller 32.
In particular, the sensor system 34 may include sensor devices for
detecting whether or not the drive shaft speed is above the
predefined threshold as part of the drive shaft test mode of
operation described above with respect to FIG. 2. The sensor system
may further detect the operational conditions by which the
controller would cause the system to enter and exit the drive shaft
test mode of operation as described with respect to FIGS. 3 and 4.
In exemplary embodiments, the sensor system 34 is the same sensor
system that provides feedback control of the drive shaft speed
during normal vehicle operation.
Commensurate with the drive shaft testing mode, the controller is
configured to determine whether the detected shaft speed is above
the predefined threshold, and if so, it is deemed that the drive
shaft is not present and available. As referenced above, the
vehicle then may be disabled. For example, the controller may send
one or more signals to any one or more of appropriate vehicle drive
components 36 (e.g., transmission, engine, PDU, etc) to disable the
vehicle. The controller also may generate a fault indicator to be
outputted to an indicator output device 38, which alerts the
vehicle operator that the drive shaft is absent and unavailable,
and the vehicle is disabled. The indicator output device may a
display to display the fault message, a dashboard light or warning
indicator, an audio device to provide an audio alert, and/or like
devices or combinations thereof.
An aspect of the invention, therefore, is a method of operating a
vehicle having a drive shaft test mode. In exemplary embodiments,
the method of operating a vehicle includes the steps of: entering
the drive shaft test mode; receiving a command to position a yoke
to drive the shaft; regulating the shaft speed so as to be below a
predefined threshold; and determining whether a drive shaft is
available based on whether an actual drive shaft speed is detected
above the predefined threshold.
In an exemplary embodiment of the method of operating a vehicle,
when the detected actual drive shaft speed is above the predefined
threshold, the method further includes determining that the drive
shaft is not available.
In an exemplary embodiment of the method of operating a vehicle,
the method further includes disabling the vehicle when it is
determined that the drive shaft is not available.
In an exemplary embodiment of the method of operating a vehicle,
the method further includes generating a fault message that alerts
a vehicle operator that the drive shaft is not available.
In an exemplary embodiment of the method of operating a vehicle,
when the detected actual drive shaft speed is not above the
predefined threshold, the method further includes determining that
the drive shaft is available and operating the vehicle with the
drive shaft limiting the speed.
In an exemplary embodiment of the method of operating a vehicle,
the step of entering the drive shaft test mode includes the steps
of: detecting a shift event of a vehicle transmission; determining
whether the shift event is a shift from neutral to in-gear
following initial startup of the vehicle; and when it is determined
that the shift event is a shift of the transmission from neutral to
in-gear following the initial startup of the vehicle, entering the
drive shaft test mode.
In an exemplary embodiment of the method of operating a vehicle,
the step of determining whether the shift event is a shift from
neutral to in-gear following the initial startup of the vehicle
includes the steps of: detecting conditions of whether the shift
event (a) is the first shifting, (b) occurred within the last three
seconds, (c) occurred with the accelerator not pressed, and (d)
occurred with the parking brake applied and the vehicle not moving;
and determining that the shift event is a shift from neutral to
in-gear following the initial startup of the vehicle when all of
conditions (a)-(d) are satisfied.
In an exemplary embodiment of the method of operating a vehicle,
the method further includes, after the step of entering the drive
shaft test mode, the steps of: detecting whether an exit condition
is present; and exiting the drive shaft test mode when the exit
condition is present.
In an exemplary embodiment of the method of operating a vehicle,
the exit condition comprises at least one of whether the
accelerator is pressed, whether the parking brake is released,
whether the vehicle has shifted out of hydraulic gears, or whether
the drive shaft speed already is detected above the predefined
threshold.
Another aspect of the invention includes a control system for
operating a vehicle having a drive shaft test mode. In exemplary
embodiments, the control system includes a sensor system for
detecting a drive shaft speed, and a controller configured to
determine whether a drive shaft is available based on whether an
actual draft shaft speed detected by the sensor system is above a
predefined threshold.
In an exemplary embodiment of the control system, when the detected
actual draft shaft speed is above the predefined threshold, the
controller determines that the drive shaft is not available.
In an exemplary embodiment of the control system, the control
system further includes one or vehicle components that when
disabled, disable a vehicle, wherein when the controller determines
that that the drive shaft is not available, the controller causes
one or more of said vehicle components to disable the vehicle.
In an exemplary embodiment of the control system, the control
system further includes an indicator output device, wherein when
the controller determines that that the drive shaft is not
available, the controller causes the indicator output device to
generate a fault message that alerts a vehicle operator that the
drive shaft is not available.
Another aspect of the invention is a non-transitory computer
readable medium storing executable program code. In exemplary
embodiments, when executed by a controller the program is
configured to perform the steps of: entering the drive shaft test
mode; receiving a command to position a yoke to drive the shaft;
regulating the shaft speed so as to be below a predefined
threshold; and determining whether a drive shaft is available based
on whether an actual drive shaft speed is detected above the
predefined threshold.
In an exemplary embodiment of the non-transitory computer readable
medium, when the detected actual drive shaft speed is above the
predefined threshold, the program code is executed to determine
that the drive shaft is not available.
In an exemplary embodiment of the non-transitory computer readable
medium, the program code is executed further to disable the vehicle
when it is determined that the drive shaft is not available.
In an exemplary embodiment of the non-transitory computer readable
medium, when the detected actual drive shaft speed is not above the
predefined threshold, the program code is executed to determine
that the drive shaft is available such that the vehicle is operable
with the drive shaft limiting the speed.
In an exemplary embodiment of the non-transitory computer readable
medium, the step of entering the drive shaft test mode includes
executing the program code to perform the steps of: detecting a
shift event of a vehicle transmission; determining whether the
shift event is a shift from neutral to in-gear following initial
startup of the vehicle; and when it is determined that the shift
event is a shift of the transmission from neutral to in-gear
following the initial startup of the vehicle, entering the drive
shaft test mode.
In an exemplary embodiment of the non-transitory computer readable
medium, after the step of entering the drive shaft test mode, the
program code is executed to perform the steps of: detecting whether
an exit condition is present; and exiting the drive shaft test mode
when the exit condition is present.
Although the invention has been shown and described with respect to
a certain embodiment or embodiments, it is obvious that equivalent
alterations and modifications will occur to others skilled in the
art upon the reading and understanding of this specification and
the annexed drawings. In particular regard to the various functions
performed by the above described elements (components, assemblies,
devices, compositions, etc.), the terms (including a reference to a
"means") used to describe such elements are intended to correspond,
unless otherwise indicated, to any element which performs the
specified function of the described element (i.e., that is
functionally equivalent), even though not structurally equivalent
to the disclosed structure which performs the function in the
herein illustrated exemplary embodiment or embodiments of the
invention. In addition, while a particular feature of the invention
may have been described above with respect to only one or more of
several illustrated embodiments, such feature may be combined with
one or more other features of the other embodiments, as may be
desired and advantageous for any given or particular
application.
* * * * *